You didnt say why you had your other kidney removed. What type of kidney disease do you have?
Blood 2+ is significant if it's persistent and require further investigation, although it depends on the amount of actual RBCs in your urine. Calcium oxalate crystals could cause this, but I would suggest that you see a nephrologist and rule out any other chronic kidney diseases.
How are you? Calcium oxalate crystals in the urine are the most common constituent of human kidney stones. Also, blood in the urine can be caused by a lot of things. Some are serious, including cancers, trauma, stones, infections, and obstructions of the urinary tract. Others are less important and may require no treatment. These may include viral infections, nonspecific inflammations of the kidney, medications and benign prostate enlargement.
As kidney stone develops, they can also cause hematuria. Hematuria can be 1)microhematuria which is blood detection on urinalysis and not by the naked eye or 2)gross hematuria as the stone passes through the urinary tract. There may be some degree of hematuria at any stage when a stone is in the urinary tract, and even after passing the stone due to the local damage caused by passage of the stone.
It is always good to see your doctor for proper evaluation and management. I hope this helps. take care and keep us posted.
My younger brother had blood in his urine which turned out to be bladder cancer. I hope you don't have that. Be sure and tell your Doctor.
Good Luck